Wsrtjtyk

I need to compress a large json array (around 30 000 rows). After searching I found this answer on stack proposing to use ob_start() to compress the json array.

After reading the documentation of ob_start(), we should use to other functions in order to properly compress and return the result, which are:

ob_get_contents();

ob_end_flush();

The function I have is:

public function getDataByType($conn, $dataType)

    {

        try

        {

            $result=array();



            if($dataType=='household')

            {

                $sql = "SELECT h.household_id, u.unit_id, h.hh_last_name_en, 

                        h.hh_last_name_ar, h.hh_number_of_ind FROM unit u 

                        INNER JOIN household h

                        ON u.unit_id=h.unit_id

                        LEFT JOIN location l

                        ON l.location_id_auto=u.location_id_auto

                        LEFT JOIN user us

                        ON us.user_id = h.user_id

                        ";

                $exec = $this->conn->prepare($sql);

                $exec->execute();

                $result = $exec->fetchAll();

                //$count = $exec->rowCount();

            }

            if($dataType=='individual')

            {



            }

            return $result;

        }

        catch(PDOException $e)

        {

            return $e->getMessage();

        }

        ob_start("getDataByType");

        $result = ob_get_contents();

        ob_end_flush();



    }

I didn't notice any change in the speed of array display on user screen, it took about 5 seconds, and still taking the same time, even more than that sometimes.

No errors shown.

I am using PHP with angular 6, and we are working locally on a LAN network.

I remove the ob_start() from the api file, and use it on from the call script according to this answer on stack:

$dataType = $_POST['dataType'];



ob_start("getDataByType");

$res = $newApi->getDataByType($conn, $dataType);

$res = ob_get_clean();

echo json_encode($res);

Why ob_start() is not compressing the json array returned, as it's having the same original uncompressed size.

This answer helped me but still didn't notice any difference on speed or json size.

EDIT

I used the following with each JSON return:

echo json_encode($res, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES | JSON_NUMERIC_CHECK );

It reduced all sizes for nearly 20%.

Using the following didn't change it:

ob_start('ob_gzhandler');

$res = $newApi->getDataByType($conn, $dataType);

ob_get_clean();

echo json_encode($res, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES | JSON_NUMERIC_CHECK );

According to this documentation, setting these lines to On didn't do that much for me:

ini_set("zlib.output_compression", 1);

ini_set("zlib.output_compression_level", 9);